Lowering systolic blood pressure to <130mmHg in patients with recent lacunar stroke significantly reduced intracerebral haemorrhage, and is likely to reduce all recurrent stroke. These findings from the SPS3 (Secondary prevention of small subcortical strokes) trial were presented at the European Stroke Conference and published simultaneously online in The Lancet.
Speaking on behalf of the investigators, Oscar R Benavente, University of British Columbia, Vancouver, Canada, told delegates that hypertension is the single most powerful risk factor for stroke, and lowering blood pressure is proven to prevent it. He noted that lacunar strokes accounted for >25% of brain infarcts and that, despite their frequency and importance, no other clinical trial had focused on this stroke subtype.
“Optimal target levels of blood pressure control to prevent stroke recurrence in patients with cerebral small vessel disease are lacking. We hypothesised that targeting systolic blood pressure <130mmHg would reduce stroke recurrence in patients with recent lacunar stroke,” Benavente said at the conference (28–31 May, London, UK).
Data from SPS3, a randomised, clinical trial conducted in eight countries, showed that although the primary endpoint, all recurrent stroke, was not significant, it did suggest a reduction in stroke in patients who had had their blood pressure lowered to the target of <130mmHg. In addition, the secondary endpoint of haemorrhagic stroke was significantly reduced in these patients.
In this arm of the trial, researchers randomised 3020 patients (mean age 63 years) who had suffered a lacunar stroke within six months to either a “higher” (130–149mmHg,) systolic blood pressure target, or a “lower” (<130mmHg) one. Antihypertensive medication for the patients was their physician’s choice.
At one year, the mean systolic blood pressure was 138mmHg in the higher group and the 127mmHg in the lower group. The mean difference in systolic blood pressure between groups was 11mmHg and this was maintained over the follow-up period of 3.7 years. The lower-target group members used, on average, 2.4 antihypertensive medications compared to 1.8 used by the higher-target group.
The rate of recurrent stroke among those assigned to higher target was 2.77% compared with 2.25% in the lower target group (p=0.08). There was 0.29% intracerebral haemorrhage seen in patients assigned to the higher target group vs. 0.11% (p=0.03).
Serious complications of blood pressure lowering were infrequent and equal between groups, and the lower target is safe and well tolerated, investigators said.
A second arm of the trial that assessed the safety and efficacy of antiplatelet regimens showed no benefit from combined aspirin and clopidogrel over aspirin alone. This data was published previously in The New England Journal of Medicine.